Self cancelling direction indicator switches

ABSTRACT

A self cancelling direction indicator switch includes a pawl member with a plurality of projecting fingers. An operating member is shaped to displace the pawl member towards the path of a striker and the pawl member is spring loaded against the member. The member operating has detent means which coact with the pawl member to hold the pawl member advanced and the member in an operative position. In this position movement of the striker in one direction causes indexing of the pawl member without releasing it from the detent means, whereas movement of the striker in the other direction rolls the pawl member out of engagement with the detent means.

United States Patent Wilkinson et al.

[ 1 Mar. 12, 1974 SELF CANCELLING DIRECTION INDICATOR SWITCHES [751 Inventors: Norman Wilkinson, Barrowford,

near Nelson; David Shaw, Accrington both of England [73] Assignee: Joseph Lucas (Industries) Limited.

Birmingham, England [22] Filed: Feb. 26, 1973 [21] Appl. No.: 335,563

Related U.S. Application Data [63] Continuation of Ser. No. 243,741, April 13, 1972,

abandoned.

[30] Foreign Application Priority Data Apr. 16, 1971 Great Britain 9627/71 [52] U.S. Cl ZOO/61.27, ZOO/61.3, ZOO/61.35 [51] Int. Cl. I-I0lh 3/16 [58] Field ofSearch 2Q0/61.2 76l.3 5 6 1.3 9

[56] References Cited UNITED STATES PATENTS 2,678,358 5/1954 Thomson ZOO/61.35

2,800,542 7/1957 Barcus ZOO/61.34 2,817,728 12/1957 Gurney ZOO/61.35

FOREIGN PATENTS OR APPLICATIONS 60.953 8/1954 France ZOO/61.3

Primary Iimminer-hmres R. Soot! Attorney, Agent, or Firm-Holman & Stern [5 7] ABSTRACT A self cancelling direction indicator switch includes a pawl member with a plurality of projecting fingers. An operating member is shaped to displace the pawl member towards the path of a striker and the pawl member is spring loaded against the member. The member operating has detent means which coact with the pawl member to hold the pawl member advanced and the member in an operative position. In this position movement of the striker in one direction causes indexing of the pawl member without releasing it from he detent means, whereas movement of the striker in the other direction rolls the pawl member out of engagement with the detent means.

5 Claims, 5 Drawing Figures PATENTEDHAR 12 m4 3 796 846 SHEET 1 OF 3 FIGI.

SELF CANCELLING DIRECTION INDICATOR SWITCHES This is a continuation, of application Ser. No. 243,74l, filed Apr. 13, I972 now abandoned.

BACKGROUND OF THE INVENTION This invention relates to self-cancelling direction indicator switches for road vehicles.

SUMMARY OF THE INVENTION A self-cancelling direction indicator switch according to the invention compries a body for attachment to a vehicle, an operating member movably mounted on the body for completing, in use, circuits to the indicator lamps, a pawl member having a plurality of projecting fingers, pawl member being rotatable to the direction in which the operating member is movable, means on the operating member for displacing the pawl member from a withdrawn position to an advanced position when the operating member is moved from a neutral position to either of a pair of operative positions on opposite sides of the neutral position, resilient means acting on the pawl member to oppose such displacement thereof by the operating member whereby the operating member is urged towards its neutral position, and detent means on the operating member engageable by the pawl member when the operating member is in either of its operative positions to hold the operating member in its operative position and the pawl member in its advanced position, the arrangement being such that, in use, when a stricker associated with the steering shaft strikes a projecting finger while travelling in one direction the pawl member is indexed to present a different finger without disengaging the detent means, Whereas, when the striker strikes the finger while travelling in the opposite direction the pawl member is released from the detent means.

BRIEF DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT.

The switch includes a body which is adapted for mounting on a fixed support surrounding a vehicle steering shaft 9. The body provides a pivotal mounting for an operating member 11 which is pivotable about an axis 12. Co-acting switch contact means 13, 14 are provided on the body and there are plungers 15, 16 operable to close either of two circuits by displacing the member 11 in opposite directions from the neutral position shown in FIG. 1 with cam pieces 17, 18 being provided on member 11 for this purpose.

The body also supports a pawl member 19. To this end the body 10 has a groove 21 extending along the imaginery line between the axis of the shaft 9 and the axis 12 and a guide part is slidable in this groove. The member 19 has a cylindrical portion 22 engaged with this guide part 20. The pawl member 19 can thus be displaced along the groove 21 in a direction transverse to the direction of movement of the operating member and can also be rotated about an axis parallel to the axis of the shaft 9 and the pivot axis 12.

The pawl member 19 has a prismatic cam portion 22 which is of regular hexagonal cross-section and co-acts with a plate 23 on the end of the operating member 11 adjacent the shaft 9. This plate of the member 11 has means for displacing the pawl member 19 from the withdrawn position of FIGS. 1 to 4 towards the shaft axis to a projecting position as shown in FIG. 5 on turning of the member 11 in either direction from its neutral position. Such means comprises a pair of flat cam surfaces 24 inclined to one another at and arranged to receive any corner of the hexagonal prismatic portion 22 of the pawl member 19. The plate 23 also has detent means whereby the member 11 is held in its operative positions and the member 19 is held in its projectingposition. Such detent means comprises a pair of ribs 25 on the plate 23 and a pair of outer flat faces 26.

Resilient means in the form of a spring 27 acts on the member 20 within the groove 21 to urge the member 19 away from the shaft 9. Thus, when the operating member 1 1 is in its neutral position, the hexagonal portion of the member 19 is urged into the angle between the two cam faces 24, at which position the spring 27 is least stressed. When the member 11 is in either of its operative positions the hexagonal portion of the member 19 engages the appropriate one of the flats 26 and the ribs 25. The member 19 is then closer to the axis of the shaft 9.

The member 19 has six projecting fingers 29 arranged with one finger projecting radially from each corner of the hexagonal cam portion 22. As will be seen from FIGS. 1 and 2 a finger 29 is always projecting towards the shaft 9 when the member 11 is in eitherof its operative positions, and lies in the path 310 of a striker 30 provided on the shaft 9.

In operation, when the member 11 is moved from its neutral position to either of its operative positions, one face of the hexagonal portion 22 of the member 19 at first remains in face contact with the appropriate one of the faces 24 of the plate 23. If, as shown in FIG. 5, the member 11 is turned in a clockwise direction, the member 19 will be displaced towards the shaft 9, initially turning slightly in a clockwise direction to maintain this face contact. When theportion 22 strikes the rib 25, the member 19 will continue to be moved towards the axis of the shaft 9, but will turn in an anticlockwise direction through 120 until a corner of the portion 22 engages the rib 25 and face 26. The member 11 can be returned manually to its neutral position and the reverse sequence of events occurs. It is only necessary for the member 1 1 to be turned sufficiently to turn member 19 through part of its indexing movement and the springloading then completes neutralization.

When the steering shaft 9 is turned in a clockwise direction and the striker 30 engages the projecting finger 29 the member 19 is merely indexed through 60 in a clockwise direction and does not release the operating member 11. When, however, the shaft is turned in the clockwise direction, the striker causes the member 19 to roll over the rib 25, thereby releasing theme'mber l 1 and allowing the spring loading to neutralize the member 11, so that the contacts l3, 14 are reopened.

The switch shown in the drawings also controls the vehicle headlights, parking lights and horn but these features do not form part of the present invention and are not, therefore described in detail.

It will be noted that if the member 11 is turned only through a small angle, i.e., until the hexagonal portion 22 engages the rib 25, the member 19 is not latched in its projecting position. Thus, on release of the operating member the latter will be returned to its neutral po sition. The cam portions 17 and 18 may be designed to actuate the plungers 15, 16 by the short movement of the operating member 11, so that the driver of the vehicle can hold the operating member in a switch actuating position for a short time to indicate that he intends to change lanes. The signal is automatically cancelled as soon as the operating member 11 is released.

We claim:

1. A self-cancelling direction indicator switch for operating a vehicle indicator lamp and attachable to the steering shaft of the vehicle and comprising:

an operating member for activating said switch and movably mounted in said switch for movement from a neutral position to either of a pair of operative positions on opposite sides of said neutral position to thereby complete circuits to said indicator lamp;

a rotatable pawl member having a plurality of projecting fingers, said pawl member being displaceable relative to said operating member in a direction transverse to the direction in which said operating member is movable;

means on said operating member for displacing said pawl member from a withdrawn position to an advanced position when said operating member is moved from said neutral position to either of said pair of operating positions during operation of said switch;

resilient spring means acting on said pawl member to oppose such displacement thereof by said operating member whereby said operating member is urged towards its neutral position;

detent means on said operating member engageable by said pawl member when said operating member is moved to either of its operative positions to hold said operating member in its operative position and said pawl member in its advanced position, so that during operation of said switch and said operating member is in either of its operative positions, when a striker member associated with the steering shaft of the vehicle strikes one of said projecting fingers of said pawl member while travelling in one direction with a rotation of said steering shaft, said pawl member is rotated to present another one of said projecting fingers without disengaging said detent means, whereas when said striker member strikes one of said projecting fingers while travelling in an opposite direction to said one direction, said pawl member is released from said detent means to thereby effect self cancelling of said indicator lamp.

2. A switch as claimed in claim 1 in which said pawl member has a prismatic cam portion which coacts with said means on the operating member for displacing the pawl and with said detent means.

3. A switch as claimed in claim 2 in which said cam portion is of hexagonal cross-section and said pawl member has six fingers radially projecting respectively from the six corners of said cam portion.

4. A switch as claimed in claim 3 in which said means on said operating member for displacing said pawl member comprises a pair of flat cam surfaces inclined to one another at so as to receive said cam portion between them with two adjacent faces thereof in face contact with said flat cam surfaces.

5. A switch as claimed in claim 4 in which said detent means comprises a pair of ribs on said operating member at the outer ends of said cam faces respectively and a pair of outer flat faces on said operating member against an appropriate one of which a face of said cam portion engages when said operating member is in either of its operative positions. 

1. A self-cancelling direction indicator switch for operating a vehicle indicator lamp and attachable to the steering shaft of the vehicle and comprising: an operating member for activating said switch and movably mounted in said switch for movement from a neutral position to either of a pair of operative positions on opposite sides of said neutral position to thereby complete circuits to said indicator lamp; a rotatable pawl member having a plurality of projecting fingers, said pawl member being displaceable relative to said operating member in a direction transverse to the direction in which said operating member is movable; means on said operating member for displacing said pawl member from a withdrawn position to an advanced position when said operating member is moved from said neutral position to either of said pair of operating positions during operation of said switch; resilient spring means acting on said pawl member to oppose such displacement thereof by said operating member whereby said operating member is urged towards its neutral position; detent means on said operating member engageable by said pawl member when said operating member is moved to either of its operative positions to hold said operating member in its operative position and said pawl member in its advanced position, so that during operation of said switch and said operating member is in either of its operative positions, when a striker member associated with the steering shaft of the vehicle strikes one of said projecting fingers of said pawl member while travelling in one direction with a rotation of said steering shaft, said pawl member is rotated to present another one of said projecting fingers without disengaging said detent means, whereas when said striker member strikes one of said projecting fingers while travelling in an opposite direction to said one direction, said pawl member is released from said detent means to thereby effect self cancelling of said indicator lamp.
 2. A switch as claimed in claim 1 in which said pawl member has a prismatic cam portion which coacts with said means on the operating member for displacing the pawl and with said detent means.
 3. A switch as claimed in claim 2 in which said cam portion is of hexagonal cross-section and said pawl member has six fingers radially projecting respectively from the six corners of said cam portion.
 4. A switch as claimed in claim 3 in which said means on said operating member for displacing said pawl member comprises a pair of flat cam surfaces inclined to one another at 120* so as to receive said cam portion between them with two adjacent faces thereof in face contact with said flat cam surfaces.
 5. A switch as claimed in claim 4 in which said detent means comprises a pair of ribs on said operating member at the outer ends of said cam faces respectively and a pair of outer flat faces on said operating member against an appropriate one of which a face of said cam portion engages when said operating member is in either of its operative positions. 